Jar with conical neck

ABSTRACT

A jar, in particular for cosmetic creams, having a neck which externally and also at least partly internally is bounded by a conical surface of diameter decreasing towards the free edge of the neck from which there projects at least one spiral thread for the screwed closure of the jar by a lid, said thread having a height which increases towards the free edge of the neck such that its cusp is inscribable on a substantially cylindrical surface

[0001] The present invention relates to a jar, in particular a glass jar intended to contain cosmetic creams or other substances in pasty form such as jams or the like.

[0002] Cosmetic creams (or other substances in creamy or pasty form intended, for example, for food use) are contained and preserved in glass or plastic jars. These jars each have a neck bounding a mouth or opening (through which the substance present in the jars can be withdrawn) which is closable by a lid screwable onto a spiral thread projecting from the outer surface of the neck.

[0003] The jars considered herein are those (the most commonly used) having a neck, the mouth or opening of which has a diameter less than the inner diameter of the jar itself.

[0004] The necks of known jars are bounded by cylindrical surfaces both inside and outside: it follows that where the inner surface of each neck joins the inner surface of the body of the jar an undercut is created immediately below the inner cylindrical surface of the neck.

[0005] This results in consequences very damaging for the user, because it is very difficult (if not impossible) to withdraw the substance which has collected at this undercut where, inter alia, air bubbles may form.

[0006] For example, the creamy substance (jam, or other food substance) present at the aforesaid undercut cannot be withdrawn with a teaspoon. However the most notable case is when the jar contains a cosmetic cream (naturally very costly) which is usually withdrawn with a finger inserted into the jar through its mouth: often, it is impossible to reach with the finger to “scrape” the inner surface of the jar immediately below the base of the neck, i.e. where the undercut between the neck and body of the jar lies.

[0007] The main object of the present invention is therefore to provide a jar, the inner surface of which is easily reachable through the opening or mouth of the jar neck.

[0008] This jar has a hollow body accessible through the opening of a neck projecting from the hollow body itself and bounding an aperture the inner diameter of which is less than the inner diameter of the hollow body, characterised in that said neck is externally and also at least partly internally bounded by a conical surface of diameter decreasing towards the free edge of the neck from which there projects at least one spiral thread for the screwed closure of the jar by a lid, said thread having a height which increases towards the free edge of the neck such that the cusp of the thread is inscribable on a substantially cylindrical surface

[0009] To clarify the understanding of the structure and characteristics of the jar of the invention, an embodiment thereof is described hereinafter by way of non-limiting example with reference to the accompanying drawing, in which:

[0010]FIG. 1 is a side elevation of a jar of the invention, shown partly in full view and partly in section;

[0011]FIG. 2 is a section through a portion of the jar of FIG. 1 on an enlarged scale;

[0012]FIG. 3 is similar to FIG. 2, but represents a portion of a jar having a known traditional structure.

[0013] Reference will firstly be made to FIG. 1 and FIG. 2 which show a jar 1 (for example of glass) intended to contain cosmetic creams.

[0014] The jar comprises a hollow body 2 accessible through the opening of a neck 3 bounding an aperture the inner diameter of which is less than the inner diameter of the body 2, as can be clearly seen from the figures.

[0015] The neck 3, which must have a length “1” sufficient to enable a lid 4, of which only a portion is shown in FIG. 1, to be screwed onto it, is characterised in that its outer surface 5 is conical, with its diameter decreasing towards the free edge of the neck, as clearly shown in FIG. 2. This enables the neck to be formed such that a substantial part 6 of its inner surface furthest from the mouth of the jar is also conical and forms a uniform extension, without undercuts, towards the opening of the neck.

[0016] As can be seen from FIGS. 1 and 2, only a short end portion of the inner surface of the neck is cylindrical.

[0017] From the outer conical surface 5 of the neck 3 there project spiral threads 7 for the screwed closure of the jar by the lid 4. The structure of the threads 7 differs from the usual threads in that (as a consequence of the fact that said threads 7 extend from a conical surface 5) the thread has a height that decreases uniformly from the free end of the neck towards the base of the neck, so that the cusp (i.e. the most outer edge) of the thread can be inscribed on a cylindrical surface, as clearly seen from FIGS. 1 and 2. This enables the lid 4 to engage the jar neck 3 as soon as the lid is rested on the neck and rotated on it.

[0018] With particular reference to FIG. 2 it is clear how each point of the inner surface of the jar 1 is easily accessible (by means of a finger or an implement such as a teaspoon) though the mouth of the neck 3, so that the entire substance contained in the jar can be easily and completely removed.

[0019] Reference will now be made to FIG. 3 which represents a portion (equivalent to that of FIG. 2) of a jar of traditional structure having a hollow body 10 from which there projects a neck 11 of traditional cylindrical shape.

[0020] As will be apparent, the entire inner surface 12 of the neck 11 has to be cylindrical, hence defining in the interior of the jar an undercut “r” which is not reachable through the mouth of the neck. It is therefore difficult or impossible to withdraw the creamy substance collected at this undercut, which is deeper and more inaccessible the greater the difference between the inner diameters of the neck 11 and of the hollow body 10. 

1. A jar for containing creamy substances, comprising a hollow body accessible through the opening of a neck projecting from the hollow body itself and bounding an aperture the inner diameter of which is less than the inner diameter of the hollow body, characterised in that said neck is externally and also at least partly internally bounded by a conical surface of diameter decreasing towards the free edge of the neck from which there projects at least one spiral thread for the screwed closure of the jar by a lid, said thread having a height which increases towards the free edge of the neck such that the cusp of the thread is inscribable on a substantially cylindrical surface 